Mixed Halides of Barium

By heating together manganese fluoride and barium chloride at 800°-1400° C., and purifying the product by repeated extraction with cold water, and, finally, alcohol at 95° C., barium fluorochloride, BaCl₂.BaF₂, is obtained in colourless plates of density 4.51 at 18° C. The melting-point is 1008° C. It is unaffected by boiling alcohol, but decomposed into fluoride and chloride by water, especially if hot. It is soluble in concentrated hydrochloric and nitric acids, and decomposed by hot sulphuric acid. Barium fluorobromide, of density 4.96, and fluoro-iodide, of density 5.21, are similarly prepared. The fluorochloride may also be obtained by fusing the amorphous fluoride with alkali chlorides.

A solution containing both barium chloride and bromide deposits mixed crystals of the composition BaCl_xBr_y.2H₂O, but on fusing the two salts together a molecular compound is formed with the evolution of heat.